Electronic fax (eFax) lets you send and receive faxes over the internet without a fax machine or phone line. Learn how it works, what makes it more secure than email, and how to get started in minutes.
Frequently Asked Questions
What is electronic fax?
Electronic fax (eFax) is a way to send and receive faxes over the internet instead of through a phone line and fax machine. You send a digital file — PDF, Word doc, or image — via email or a web app, and the service delivers it to any fax number worldwide.
Is electronic fax secure?
Yes. Modern electronic fax services use 256-bit AES encryption — the same standard as online banking — plus TLS for data in transit. Reputable providers also offer HIPAA compliance with Business Associate Agreements, making them suitable for healthcare and legal documents. See our [HIPAA-compliant fax guide](/blog/best-hipaa-compliant-online-fax-service/) for the full checklist.
What is the difference between electronic fax and traditional fax?
Traditional fax uses a physical machine and an analog phone line. Electronic fax uses the internet. The result is the same — a document delivered to a fax number — but eFax is faster, cheaper, accessible from any device, and requires no hardware, paper, or dedicated phone line.
What file formats can I send by electronic fax?
Most electronic fax services accept PDF, TIFF, DOC, DOCX, PNG, JPG, and other common file formats. PDF is recommended for the cleanest rendering at the recipient's end.
Can anyone with a regular fax machine send to my electronic fax number?
Yes. Your electronic fax number is a standard fax number. Anyone using a traditional fax machine or another internet fax service can reach you at that number without knowing you use an online service.